Author Topic: Third Member  (Read 683 times)

Offline money pit

  • Jr. Member
  • **
  • Posts: 239
Third Member
« on: February 29, 2020 - 02:32:23 pm »
I see a lot of third members housings with the gears for the 8 3/4 rearends. Are the the third members for a B body and E body the same. Is there a difference in the axles splines for the B and E body?  I'm having problems finding an E body rearend so I was looking for a B body rearend.  Thanks

Offline 70chall440

  • Sr. Resident
  • ******
  • Posts: 5969
Re: Third Member
« Reply #1 on: March 01, 2020 - 12:08:30 am »
Ok, the B and E body housings are slightly different, the B body ones are narrower so a lot of E body guys use them to get fatter rear tires under the back. That said, I believe that you will need to use a spring relocation kit and weld in the spring perches but I am not 100% on that.

As to the 3rd members, first off they will all fit and work, there are 3 variations the 741, 742 and 489. The 489 is considered the strongest and most desirable but the other 2 will work just as well. In other words, any 8 3/4 3rd member will work for you however some of the very early 8 3/4's might be a bit different in the axles but I am not exactly sure of that.

I don't know what your financial situation is but there are a lot of 3rd members around, check craigslist, offer up, etc. Most Mopar guys have several laying around (I know I do). Places like Strange and Dr. Diff sell new or rebuilt units as well. No idea where you are or going with the drive train but if you want a Suregrip (aka posi) then it will more expensive.
Current Mopar
70 Challenger RT 440-6 EFI, 73 Cuda 416-6 EFI
05 Hemi Durango, 01 Ram 4x4, 14 Ram 2500 4X4, 10 PCP Challenger 6 spd RT, 01 Viper GTS ACR, 52 B3B w/330 Desoto Hemi, 70 Hemi RR (under const)
Past Mopars
9 x Challengers. AAR Cuda, 4 RR, 2 GTX, 4 Chargers, etc... (too many to list)